Networking

Detailed Description

Seastar provides a simple networking API, backed by two TCP/IP stacks: the POSIX stack, utilizing the kernel's BSD socket APIs, and the native stack, implement fully within seastar and able to drive network cards directly. The native stack supports zero-copy on both transmit and receive, and is implemented using seastar's high performance, lockless sharded design. The network stack can be selected with the --network-stack command-line parameter.

Classes
struct	seastar::connected_socket_input_stream_config
class	seastar::connected_socket
class	seastar::socket
struct	seastar::accept_result
	The result of an server_socket::accept() call. More...
class	seastar::server_socket
	A listening socket, waiting to accept incoming network connections. More...

Functions
server_socket	seastar::listen (socket_address sa)
server_socket	seastar::listen (socket_address sa, listen_options opts)
future< connected_socket >	seastar::connect (socket_address sa)
future< connected_socket >	seastar::connect (socket_address sa, socket_address local, transport proto)
socket	seastar::make_socket ()
net::udp_channel	seastar::make_udp_channel ()
net::udp_channel	seastar::make_udp_channel (const socket_address &local)

---

Class Documentation

seastar::connected_socket_input_stream_config

struct seastar::connected_socket_input_stream_config

Class Members
unsigned	buffer_size	Initial buffer size to use for input buffering.
unsigned	max_buffer_size	Maximum buffer size to use for input buffering. The system will increase buffer sizes if it sees a tendency towards large requests, but will not go above this buffer size.
unsigned	min_buffer_size	Minimum buffer size to use for input buffering. The system will decrease buffer sizes if it sees a tendency towards small requests, but will not go below this buffer size.

seastar::accept_result

struct seastar::accept_result

Class Members
connected_socket	connection	The newly-accepted connection.
socket_address	remote_address	The address of the peer that connected to us.

Function Documentation

connect() [1/2]

future<connected_socket> seastar::connect

(

socket_address

sa

)

Establishes a connection to a given address

Attempts to connect to the given address.

Parameters

sa	socket address to connect to

Returns

a connected_socket object, or an exception

connect() [2/2]

future<connected_socket> seastar::connect	(	socket_address	sa,
		socket_address	local,
		transport	proto
	)

Establishes a connection to a given address

Attempts to connect to the given address with a defined local endpoint

Parameters

sa	socket address to connect to
local	socket address for local endpoint
proto	transport protocol (TCP or SCTP)

Returns

a connected_socket object, or an exception

listen() [1/2]

server_socket seastar::listen

(

socket_address

sa

)

Listen for connections on a given port

Starts listening on a given address for incoming connections.

Parameters

sa	socket address to listen on

Returns

server_socket object ready to accept connections.

See also

listen(socket_address sa, listen_options opts)

listen() [2/2]

server_socket seastar::listen	(	socket_address	sa,
		listen_options	opts
	)

Listen for connections on a given port

Starts listening on a given address for incoming connections.

Parameters

sa	socket address to listen on
opts	options controlling the listen operation

Returns

server_socket object ready to accept connections.

See also

listen(socket_address sa)

make_socket()

socket seastar::make_socket

(

)

Creates a socket object suitable for establishing stream-oriented connections

Returns

a socket object that can be used for establishing connections

make_udp_channel() [1/2]

net::udp_channel seastar::make_udp_channel

(

)

Creates a udp_channel object suitable for sending UDP packets

The channel is not bound to a local address, and thus can only be used for sending.

Returns

a net::udp_channel object that can be used for UDP transfers.

make_udp_channel() [2/2]

net::udp_channel seastar::make_udp_channel

(

const socket_address &

local

)

Creates a udp_channel object suitable for sending and receiving UDP packets

Parameters

local

local address to bind to

Returns

a net::udp_channel object that can be used for UDP transfers.